/**
 * 判断是否为空
 * true 空，false 不为空
 * @param obj_val
 * @returns {Boolean}
 */
function isNUll(obj_val) {
	if(typeof(obj_val)!=undefined){
		obj_val = obj_val.replace(/\ /g,"");
		if(obj_val.length == 0)
			return true;
		else 
			return false;
	}else{
		return true;
	}
}